Characterizing the soundscape of tranquil urban spaces

Abstract

Tranquil spaces provide restorative environments for urban residents and visitors and are therefore essential for health and quality of life. Tranquil spaces may be characterized through a combination of acoustical criteria, such as relatively low (percentile) sound levels and the relative absence of non-fitting sounds, and non-acoustical criteria, such as the presence of natural elements within the visual scene. Public urban parks and courtyards as well as private urban backyards are typically considered to be the most tranquil spots within a city. Current state-of-the-art in distributed measurement technology allows for long-term sound monitoring at these places. In this paper, the soundscape at a number of urban parks and backyards in the cities of Ghent and Antwerp is investigated through a detailed analysis of sound measurements performed over an extended period of time. An analysis of percentile sound levels, noise events and indicators for temporal and spectral structure is presented, and novel computational methods are applied to estimate the relative occurrence of sounds arising from various sources.